1. Field of the Invention
The present invention relates to a display apparatus and a method of driving the same. More particularly, the present invention relates to a display apparatus that may have improved brightness and an improved contrast ratio and a method of driving the display apparatus.
2. Description of the Background
Generally, a liquid crystal display (LCD) apparatus includes a lower substrate, an upper substrate facing the lower substrate, and a liquid crystal layer interposed between the lower substrate and the upper substrate.
The lower substrate includes a plurality of pixels arranged in a plurality of pixel areas, respectively. The pixel areas are defined by gate lines and data lines that cross and are insulated from the gate lines. Each pixel includes a thin film transistor and a pixel electrode. The upper substrate includes a color filter layer, which includes a red color pixel, a green color pixel, and a blue color pixel, and a common electrode arranged on the color filter layer.
A conventional LCD apparatus further includes a backlight unit, which is arranged under the lower substrate, to generate a white light. The white light output from the backlight unit passes through the liquid crystal layer, and the transmittance of the white light is varied by the intensity of an electric field formed between the lower substrate and the upper substrate. The white light having the controlled transmittance passes through the red, green, and blue color pixels, so that a predetermined color may be displayed.
Recently, a color sequential display (CSD) mode LCD apparatus, in which an active period during which one pixel is turned on is divided into a red sub frame, a green sub frame, a blue sub frame, and a white sub frame, has been suggested. The CSD mode LCD apparatus further includes a backlight unit that sequentially generates a red light, a green light, a blue light, and a white light during the red, green, blue, and white sub frames, respectively. Since the CSD mode LCD apparatus adopting the backlight unit controls the transmittances of the red, green, blue, and white lights to express a predetermined color, the color filter layer arranged on the upper substrate may be omitted in the CSD mode LCD apparatus.
However, in a conventional CSD mode LCD apparatus, an LCD panel is selectively turned on according to the red, green, blue, and white sub frames. Moreover, when the LCD panel is operated in a black-white mode and displays an image having a white gray scale, the LCD panel is turned off during the red, green, and blue sub frames and turned on during only the white sub frame, which may result in deterioration of the brightness of the LCD apparatus.